When Elliot is talking to Sean on the cellphone after she skids to a stop beside the bus, the door of her car is alternately open and closed as the camera angle switches from her to Sean's perspective.
When Elliot skids the car to a stop in front of the bus, you can clearly see the skid marks from a previous take.
When JD runs into The Janitor & Troy in reception, the boom mic with its green tape marking can been seen at the top of shot.